How many four-sided figures appear in the diagram?

There are a number of these geometric combinometrics problems around.  Here is a complete graphic solution to the one of the more common ones.

Question: How many four-sided figures appear in the diagram below?

  1. 10
  2. 16
  3. 22
  4. 25
  5. 28

Answer: 25

Yaacov Apelbaum - How many four sided figures

 

© Copyright 2017 Yaacov Apelbaum, All Rights Reserved.

2 thoughts on “How many four-sided figures appear in the diagram?

  1. answer is 22 not 25 as question was How many “four-sided” figures appear in the diagram below? and in shape above we more than “four-sided” shapes.

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    • Thanks for your comment Mahmoud, There are 25 unique 4 sided rectangle configurations in the diagram (marked in red).

      Here is the summation method I used to arrive at this figure:
      1’st row = 9
      2’nd row = 9
      3’rd row = 7
      —————
      Total = 25

      Like

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